1. Field of the Invention
The present invention relates to catalysts, a method of making catalysts, and a process for polymerizing olefins. In another aspect, the present invention relates to polyolefin catalysts, a method of making polyolefin catalysts, and a method of polymerizing olefins. In even another aspect, the present invention relates to polyolefin catalysts derived from diketonate complexes, a method of making polyolefin catalysts from diketonate complexes, and a method of polymerizing olefins from such catalysts. In still another aspect, the present invention relates to polyolefin catalysts derived from (bis)diketonate complexes of magnesium with titanium halides, a method of making polyolefin catalysts from (bis) diketonate complexes of magnesium with titanium halides, and a method of polymerizing olefins from such catalysts.
2. Description of the Related Art
Having been around since the early 1950""s, Ziegler-type polyolefin catalysts, their general methods of making, and subsequent use, are well known in the polymerization art.
However, while much is known about Ziegler-type catalysts, there is a constant search for improvements in their polymer yield, catalyst life, catalyst activity, and in their ability to produce polyolefins having certain properties.
U.S. Pat. No. 4,472,521, issued Sep. 18, 1984 to Band, discloses a polyolefin catalyst made by contacting a Mg(OR)2 and/or Mn(OR)2 with titanium tetrachloride, then with a titanium tetrachloride halogenating agent, and then with an electron donor.
U.S. Pat. No. 4,673,661, issued Jun. 16, 1987, and U.S. Pat. No. 4,724,255, issued Feb. 9, 1988, both to Lofgren et al. disclose a polyolefin catalyst component made by chlorinating a magnesium alkyl which is then contacted with titanium tetrachloride, a Lewis base, and then at least once with titanium tetrachloride in the absence of a Lewis base. Lofgren et al. teach the criticality of an electron donor at the first titanium tetrachloride treatment step and further teach that away from the presence of an electron donor at subsequent titanation steps.
U.S. Pat. No. 4,855,271, issued Aug. 8, 1989, and U.S. Pat. No. 4,937,300, both to McDaniel et al. disclose a polyolefin catalyst derived from alumina impregnated with magnesium alkoxide, which is subsequently contacted with a lower order alcohol, chlorinated with silicon tetrachloride, and subsequently etched with a titanium tetrachloride.
U.S. Pat. No. 5,075,270, issued Dec. 24, 1991 to Brun et al. discloses a polyolefin catalyst made by reacting a magnesium alkoxide with an aluminosiloxane derivative, which product is then chlorinated with silicone tetrachloride, followed by transition metal treatment with titanium tetrachloride, with an electron donor optionally associated with the transition metal.
Even with these prior art methods there is still a need for improved polyolefin catalysts, methods of their making, and methods of polymerizing.
There is another need for polyolefin catalysts having improved activity.
There is even another need for polyolefin catalysts having controlled morphology.
These and other needs in the art will become apparent to those of skill in the art upon review of this patent specification.
It is one object of the present invention to provide for improved polyolefin catalysts, methods of their making, and methods of polymerizing.
It is another object of the present invention to provide for polyolefin catalysts having improved polymer yields.
It is another object of the present invention to provide for polyolefin catalysts having controlled morphology.
These and other objects of the present invention will become apparent to those of skill in the art upon review of this patent specification.
According to one embodiment of the present invention, there is provided a process for preparing a catalyst component. This process generally includes contacting a metal compound of the formula MR2 with a diketone to form a metal bis (diketonate), wherein M is a Group IIA metal, and R is a hydrocarbyl or substituted hydrocarbyl having from 1 to 20 carbons atoms. The process further includes contacting the metal bis(ketonate) with a halogenating agent to form a catalyst component.
According to another embodiment of the invention, there is provided a process for forming a polyolefin catalyst. Generally the process comprises: a) contacting a catalyst component with an organometallic compound to form a catalyst. The catalyst component is produced by a process comprising: i) contacting a metal compound of the formula MR2 with a diketone to form a metal bis(diketonate) having the formula M(OCRCRxe2x80x2CRO)2, wherein M is a Group IIA or Group VIIB metal, and wherein R and Rxe2x80x2 are each hydrocarbyls or substituted hydrocarbyls having from 1 to 20 carbons atoms; ii) contacting the metal bis(ketonate) with a first halogenating agent to form reaction product A, and may further comprise the step of iii) contacting reaction product A with a second halogenating agent.
According to even another embodiment of the invention, there is provided a process of making a catalyst system. The process comprises contacting a polyolefin catalyst with an inert support. Preferably the inert support is a magnesium compound. The catalyst is produced by a process comprising: i) contacting a metal compound of the formula MR2 with a diketone to form a metal bis(diketonate) having the formula M(OCRCRxe2x80x2CRO)2, wherein M is a Group IIA or Group VIIB metal, and wherein R and Rxe2x80x2 are each hydrocarbyls or substituted hydrocarbyls having from 1 to 20 carbons atoms; and ii) contacting the metal bis(ketonate) with a first halogenating agent to form reaction product A. The process of making the catalyst may further comprise the steps of: iii) contacting reaction product A with a second halogenating agent to form a catalyst component, and iv) contacting the catalyst component with an organometallic agent, such as, for example. TEAl, to form a catalyst.
According to still another embodiment of the invention, there is provided a process for xcex1-olefin polymerization. The process comprises: a) contacting one or more xcex1-olefin monomers together in the presence of a catalyst of the invention. Generally the catalyst of the invention is produced by a process comprising: i) contacting a metal compound of the formula MR2 with a diketone to form a metal bis(diketonate) having the formula M(OCRCRxe2x80x2CRO)2, wherein M is a Group IIA or Group VIIB metal, and R and Rxe2x80x2 are hydrocarbyls or substituted hydrocarbyls having from 1 to 20 carbons atoms; and ii) contacting the metal bis(ketonate) with a, first halogenating agent to form reaction product A.
A suitable diketonate can have a structure such as, for example: 
According to yet another embodiment of the invention, there is provided a polyolefin catalyst component produced by a process comprising contacting a metal compound of the formula MR2 with a diketone to form a metal bis(diketonate) having the formula M(OCRCRxe2x80x2CRO)2, and contacting the metal bis(ketonate) with a first halogenating agent to form reaction product A. The catalyst component making process may further comprise a step of contacting reaction product A with a second halogenating agent to form a catalyst component. In the above formula, generally M is a Group IIA or Group VIIB metal, and R and Rxe2x80x2 are each hydrocarbyls or substituted hydrocarbyls having from 1 to 20 carbons atoms.
According to even still another embodiment of the invention, there is provided a polyolefin catalyst produced by a process comprising contacting a catalyst component produced by a method of the invention with an organometallic compound.
According to even yet another embodiment of the invention, there is provided a catalyst system comprising an inert support and a polyolefin catalyst of the invention, wherein the polyolefin catalyst is produced by a method of the invention. Preferably the inert support is a magnesium compound.
According to still even another embodiment of the invention, there is provided a polymer produced by a process comprising contacting one or more xcex1-olefin monomers together in the presence of a catalyst of the invention. The process further comprises extracting polyolefin polymers. Preferably, the polymer of the invention has a molecular weight distribution of at least 4.